Rational approach to fetal heart rate monitoring and management during the second stage of labor.

Second stage of labor is considered to be associated with an increased risk of intrapartum fetal hypoxic injury. This is due to a combination of several risk factors such as -the increased frequency, strength and duration of uterine contractions due to higher number and affinity of myometrial oxytocin receptors; -the Ferguson's reflex which leads to a reflex release of endogenous oxytocin in response of the distension of the cervix by descending fetal head in late stages of labor; maternal expulsive efforts with the Valsalva manoeuvre that may reduce maternal oxygenation, as well as reduce the venous return and maternal cardiac output due to increased intrathoracic pressure, winch may lead to reduced placental oxygenation; - and increased fetal intracranial pressure due to head compression leading to a potential decrease in fetal cerebral oxygenation. In addition, the umbilical cord often forms one or more loops around the fetal neck, which may get tightened as the head descends leading to an acute and intermittent cessation of fetal oxygenation.

International expert consensus statement on physiological interpretation of cardiotocograph (CTG): First revision (2024).

The first international consensus guideline on physiological interpretation of cardiotocograph (CTG) produced by 44 CTG experts from 14 countries was published in 2018. This guideline ensured a paradigm shift from classifying CTG by arbitrarily grouping certain features of the fetal heart rate into different "categories", and then, randomly combining them to arrive at an overall classification of CTG traces into "Normal, Suspicious and Pathological" (or Category I, II and III) to a classification which is based on the understanding of fetal pathophysiology. The guideline recommended the recognition of different types of fetal hypoxia, and the determination of features of fetal compensatory responses as well as decompensation to ongoing hypoxic stress on the CTG trace.

Relative uteroplacental insufficiency of labor.

Relative uteroplacental insufficiency of labor (RUPI-L) is a clinical condition that refers to alterations in the fetal oxygen "demand-supply" equation caused by the onset of regular uterine activity. The term RUPI-L indicates a condition of "relative" uteroplacental insufficiency which is relative to a specific stressful circumstance, such as the onset of regular uterine activity. RUPI-L may be more prevalent in fetuses in which the ratio between the fetal oxygen supply and demand is already slightly reduced, such as in cases of subclinical placental insufficiency, post-term pregnancies, gestational diabetes, and other similar conditions.

Correlation between intrapartum CTG findings and interleukin-6 levels in the umbilical cord arterial blood: A prospective cohort study.

Objective: to investigate the correlation between the intrapartum CardioTocoGraphic (CTG) findings "suggestive of fetal inflammation" ("SOFI") and the interleukin (IL)-6 level in the umbilical arterial blood.

Study Design: prospective cohort study conducted at a tertiary maternity unit and including 447 neonates born at term.

Methods: IL-6 levels were systematically measured at birth from a sample of blood taken from the umbilical artery.

Optimizing the management of acute, prolonged decelerations and fetal bradycardia based on the understanding of fetal pathophysiology.

Any acute and profound reduction in fetal oxygenation increases the risk of anaerobic metabolism in the fetal myocardium and, hence, the risk of lactic acidosis. On the contrary, in a gradually evolving hypoxic stress, there is sufficient time to mount a catecholamine-mediated increase in the fetal heart rate to increase the cardiac output and redistribute oxygenated blood to maintain an aerobic metabolism in the fetal central organs. When the hypoxic stress is sudden, profound, and sustained, it is not possible to continue to maintain central organ perfusion by peripheral vasoconstriction and centralization.

Physiological CTG categorization in types of hypoxia compared with MRI and neurodevelopmental outcome in infants with HIE.

Background: Commonly used methods of CTG classification do not reliably predict neonatal hypoxic-ischemic encephalopathy (HIE).

Objective: To examine whether a relationship exists between the types of hypoxia as identified on the cardiotocograph using novel physiology-based CTG classification and patterns of injury on neonatal cerebral MRI and later neurodevelopmental outcomes.

Study Design: A retrospective study of term-born infants admitted to four neonatal units with HIE as part of a brain injury biomarkers study between January 2014 and December 2015.

Absence of fetal heart rate cycling on the intrapartum cardiotocograph (CTG) is associated with intrapartum pyrexia and lower Apgar scores.

Background: Cycling consists of alternating periods of reduced and normal fetal heart variability, reflecting changes in fetal behavioral states. Occurrence of active and quiet sleep cycles is considered to be a hallmark of fetal autonomic nervous system integrity, demonstrating healthy interaction between the parasympathetic and sympathetic nervous systems. Cycling is an overlooked feature in most international cardiotocography (CTG) guidelines.

Cardiotocograph (CTG) changes and maternal and neonatal outcomes in chorioamnionitis and/or funisitis confirmed on histopathology.

Objective: To assess the cardiotocographic changes and maternal and neonatal outcomes in cases of chorioamnionitis and or funisitis confirmed on histopathology.

Study Design: A retrospective analysis of histopathology reports confirming chorioamnionitis and/or funisitis was carried out from 2014 to 2020 in a single centre. The preterm births (<37 weeks) were excluded.

Fetal heart rate monitoring in labor: from pattern recognition to fetal physiology.

The journey of human labor involves hypoxic and mechanical stresses as a result of progressively increasing frequency, duration and strength of uterine contractions and resultant compression of the umbilical cord. In addition, occlusion of the spiral arteries during myometrial contractions also leads to repetitive interruptions in the utero-placental circulation, predisposing a fetus to progressively worsening hypoxic stress as labor progresses. The vast majority of fetuses are equipped with compensatory mechanisms to withstand these hypoxic and mechanical stresses.

Conservative surgical approach: The Triple P procedure.

The incidence of abnormally invasive placenta (AIP) or currently called placenta accreta spectrum (PAS) disorders has increased worldwide over the last few decades. Although the exact physiopathology is not yet well established, there is consensus that an increase in the Caesarean section rates, uterine surgery and the advanced maternal age are important contributory factors. Traditionally, the treatment for PAS has been a peripartum hysterectomy.

Etiopathogenesis and risk factors for placental accreta spectrum disorders.

Placenta accreta spectrum (PAS) disorders, comprising placenta accreta, increta, and percreta, are associated with serious maternal morbidity and mortality in both the developed and the developing world. The incidence of PAS has increased in the recent years, and the rising rates of cesarean section rate, placenta accreta in previous pregnancies, and other uterine surgeries including myomectomies and repeated endometrial curettage are implicated in its etiopathogenesis. The absolute risk of PAS increases with the number of previous cesarean sections.

How to set up a regional specialist referral service for Placenta Accreta Spectrum (PAS) disorders?

There has been an approximately fivefold increase in the incidence of placenta accreta spectrum (PAS) disorders during the last 30 years, believed to be secondary to increasing Caesarean section rates. PAS disorder is associated with significantly increased maternal morbidity and mortality worldwide. Antenatal diagnosis by foetal medicine teams that have a special expertise to diagnose PAS disorder by the use of ultrasound scan, and a dedicated, highly specialised multidisciplinary team (MDT) comprising surgeons who are skilled in complex pelvic surgery and obstetric anaesthetists who have an expertise in high-risk obstetric anaesthesia, supported by haematology, operating theatre, interventional radiology, midwifery, neonatology, high-dependency and intensive care teams have been recommended to improve maternal and perinatal outcomes.

Fetal heart rate changes on the cardiotocograph trace secondary to maternal COVID-19 infection.

Objective: To determine the cardiotocograph (CTG) changes in women with symptomatic COVID-19 infection.

Study Design: 12 anonymised CTG traces from 2 hospitals in Spain were retrospectively analysed by 2 independent assessors. CTG parameters were studied based on fetal pathophysiological responses to inflammation and hypoxia that would be expected based on the pathogenesis of COVID-19 patients.

Does the saltatory pattern on cardiotocograph (CTG) trace really exist? The ZigZag pattern as an alternative definition and its correlation with perinatal outcomes.

Background: The saltatory pattern (SP) has been defined by guidelines as a uniformly increased bandwidth of >25 beats per min lasting for 30 min. However, previous research suggest that it is very unusual to observe such a "uniform" increase in the bandwidth persisting for >30 min. Baseline fetal heart rate variability (FHRV) on cardiotocography reflects the integrity of the central nervous system.

Intrapartum cardiotocography patterns observed in suspected clinical and subclinical chorioamnionitis in term fetuses.

Aim: To evaluate the cardiotocography (CTG) features observed in suspected intrapartum chorioamnionitis in term fetuses according to the recently suggested criteria for the pathophysiological interpretation of the fetal heart rate and their correlation with perinatal outcomes.

Methods: Retrospective analysis of nonconsecutive CTG traces. 'CTG chorioamnionitis' was diagnosed either based on a persistent rise in the baseline for the given gestation or on a persistent increase in the baseline fetal heart rate during labor >10% without preceding CTG signs of hypoxia and in the absence of maternal pyrexia.

Types of intrapartum hypoxia on the cardiotocograph (CTG): do they have any relationship with the type of brain injury in the MRI scan in term babies?

Electronic foetal monitoring using cardiotocography is aimed at the timely recognition and management of foetal hypoxia. The primary objective of this study was to examine whether a relationship exists between the types of foetal hypoxia (acute, subacute, evolving, chronic), as identified on cardiotocography and the nature of hypoxic ischaemic encephalopathy, as observed on MRI scans after birth. We conducted a retrospective study of 16 babies born (out of 52,187 births) at St George's Hospital in London during 2006-2017 with a postnatal diagnosis of HIE.

Outcomes of the first 50 patients with abnormally invasive placenta managed using the "Triple P Procedure" conservative surgical approach.

Objective: To determine maternal outcomes for women with abnormally invasive placenta (AIP) managed using the Triple P Procedure and establish its safety as a conservative surgical management option.

Methods: A retrospective study of the outcomes of the first 50 patients who underwent the Triple P Procedure for AIP from September 2010 to May 2017 at St George's Maternity Unit. Maternity case notes and the database were reviewed to determine the volume of bleeding, procedure-related complications, hysterectomy rate, and postoperative hospitalization.

Placenta accreta spectrum: Risk factors, diagnosis and management with special reference to the Triple P procedure.

Abnormal invasion of placenta or placenta accreta spectrum disorders refer to the penetration of the trophoblastic tissue through the decidua basalis into the underlying uterine myometrium, the uterine serosa or even beyond, extending to pelvic organs. It is classified depending on the degree of invasion into placenta accreta (invasion <50% of the myometrium), increta (invasion >50% of the myometrium) and percreta (invading the serosa and adjacent pelvic organs). Clinical diagnosis is made intra-operatively; however, the confirmative diagnosis can only be made after a histopathological examination.

Physiological CTG interpretation: the significance of baseline fetal heart rate changes after the onset of decelerations and associated perinatal outcomes.

Objective: To determine the perinatal outcomes in fetuses with baseline fetal heart rate changes with preceding decelerations on the cardiotocography (CTG) trace, and to interpret CTG traces from the aspect of fetal physiology.

Materials And Methods: A retrospective analysis of 500 consecutive CTG traces was carried out. The presence of repetitive variable and late decelerations followed by the changes in the baseline including baseline tachycardia and abnormal baseline variability were determined.